From d19c4643a52f0a56a7ccc86b145f207a57f40116 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Wed, 29 Mar 2017 00:19:24 -0500 Subject: target: Fix ALUA transition state race between multiple initiators Multiple threads could be writing to alua_access_state at the same time, or there could be multiple STPGs in flight (different initiators sending them or one initiator sending them to different ports), or a combo of both and the core_alua_do_transition_tg_pt calls will race with each other. Because from the last patches we no longer delay running core_alua_do_transition_tg_pt_work, there does not seem to be any point in running that in a workqueue. And, we always wait for it to complete one way or another, so we can sleep in this code path. So, this patch made over target-pending just adds a mutex and does the work core_alua_do_transition_tg_pt_work was doing in core_alua_do_transition_tg_pt. There is also no need to use an atomic for the tg_pt_gp_alua_access_state. In core_alua_do_transition_tg_pt we will test and set it under the transition mutex. And, it is a int/32 bits so in the other places where it is read, we will never see it partially updated. Signed-off-by: Mike Christie Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_configfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/target/target_core_configfs.c') diff --git a/drivers/target/target_core_configfs.c b/drivers/target/target_core_configfs.c index 38b5025e4c7a..70657fd56440 100644 --- a/drivers/target/target_core_configfs.c +++ b/drivers/target/target_core_configfs.c @@ -2392,7 +2392,7 @@ static ssize_t target_tg_pt_gp_alua_access_state_show(struct config_item *item, char *page) { return sprintf(page, "%d\n", - atomic_read(&to_tg_pt_gp(item)->tg_pt_gp_alua_access_state)); + to_tg_pt_gp(item)->tg_pt_gp_alua_access_state); } static ssize_t target_tg_pt_gp_alua_access_state_store(struct config_item *item, -- cgit v1.2.3